HELP! Initialize renderer failed -- virtualbox

[montezuma15]

I recently switched over to mac from pc. not wanting to purchase civ 4 and bts for mac, i decided to download sun microsystems' virtualbox and use that to run my old bts for windows xp. after installation, when i try to run civ4 i get the initialize renderer failed error message. i have read many of the other postings about this error, but i have a different graphics driver since i am using virtualbox. I tried updating my directX and it didn't do any good. HELP!